Polygenic powdery mildew disease resistance in Arabidopsis thaliana: quantitative trait analysis of the accession Warschau‐1

Abstract

To further the understanding of the natural genetic diversity for disease resistance to powdery mildew (Erysiphe cichoracearum) in Arabidopsis thaliana, quantitative trait loci analysis was undertaken on recombinant inbred lines derived from a cross between the resistant accession Warschau-1 and the susceptible Columbia-0. Powdery mildew grew less well on Warschau-1, but the resistance was not associated with a specific block in the infection sequence. Two potential powdery mildew disease-resistance loci were identified and mapped, one with a major effect and one with a minor effect on disease resistance. The two loci acted in an additive manner to confer resistance, and together they explained 65% of the variation in resistance. In addition, the major powdery mildew disease-resistance locus was genetically mapped to the bottom of chromosome III, a region containing the powdery mildew resistance loci RPW7, RPW8 and RPW10. Unlike resistance mediated by the RPW8 locus in the accession Moscow-1, resistance in Warschau-1 was not correlated with the hypersensitive response, highlighting the influence of genetic background or environmental factors on the expression of disease resistance. Together with the powdery mildew resistance loci described in other studies, these results suggest that A. thaliana is a useful source of natural powdery mildew disease resistance, which potentially can be utilized in fundamental studies and as a tool for applied studies.

Aneuploidy and Genetic Variation in the Arabidopsis thaliana Triploid Response

“…embryos die because of abnormal endosperm developThe CWW F 2 aneuploid swarm ( Figure 2a) likely rement and the few individuals that do develop exhibit flects the composition of the F 2 generation used to genhighly reduced fertility (Satina and Blakeslee 1938; erate the recombinant inbred lines produced by Schiff Woodell and Valentine 1961; Tsuchiya 1967). This and coworkers (Schiff et al 2001). Analysis of these phenomenon is called the triploid block.…”

“…The sucrose, 0.20% Triton-X, 0.5 mm spermine, and 0.10% freshly Col-0 ϫ Wa-1 recombinant inbred lines described by Schiff added ␤-mercaptoethanol, pH 6.1). The tissue was chopped and coworkers (Schiff et al 2001) were obtained directly from using a fresh carbon-steel razor blade (VWR) for ‫1ف‬ min. Shauna Somerville (Carnegie Institution, Stanford, CA).…”

SSR markers linked to mite (Polyphagotarsonemus latus Banks) resistance in jute (Corchorus olitorius L.)

“…It will be helpful in future to identify the locations of genes responsible for the mite resistance trait in jute by positional cloning. Most of the pest and disease resistant traits are controlled by many genes (Schiff et al 2001;Lindhout et al 2002). They could be genetically complex quantitative traits, involving many genes and environmental effects.…”

Assessment of Partial Resistance to Powdery Mildew (Podosphaera pannosa) in a Tetraploid Rose Population Using a Spore-suspension Inoculation Method

“…However, it is quite likely that rose as well as other species may have several additional genes contributing to the overall resistance against this pathogen. For example, both qualitative and quantitative resistances to powdery mildew have been found in species such as barley (Jorgensen, 1994;Williams, 2003), wheat (Mingeot et al, 2002), tomato (Bai, 2004) and Arabidopsis thaliana (Schiff et al, 2001). Therefore, studies including other resistant rose genotypes are needed to get a more complete picture of the inheritance of powdery mildew resistance in cultivated roses.…”